No, you do need to combine with BROWNS but there are all kinds of BROWNS not just fall leaves.
I save the kitchen scraps for compost in "compost bag" which is grocery store paper bag lined plastic bag, with paper pulp egg carton or fast food beverage carrier in the bottom for air space and to absorb excess moisture. While not decorative, this lasts (doesn't get stinky or moldy) for a few days because it's not overly wet, not tightly enclosed -- and it is easier to toss stuff in for everybody involved. (On the opposite end of the process, I can't handle putting stinky moldy compost ingredients in the compost pile).
"Compost Bag" is used for all kitchen scraps including nut shells, paper coffee filters and teabags, used and grease stained papers like pizza boxes that can't be put in paper recycling, mixed with all used paper towels and napkins, discarded paper bags, paper towel core and other mostly unprinted cardboard, occasional "deemed safe" printed paper, etc. So there are already a fair amount of "BROWNS" in there. During the winter, overwintering-in-the-house plants shed leaves and clippings, too.
(FWIW, I tried to install an under cabinet trash bin drawer to keep the Compost Bag out-of-sight, but my family is too used to the convenience of having the bag out in the open.
Toilet paper cores are saved separately in the bathrooms but I put them in the compost pile, and that bag also gets other scraps of household (non glossy) "deemed safe" paper waste -- things like natural tooth paste cardboard box, etc., trimmed hair.... So this bag is the main receptacle for the rest of the dry household BROWN compost ingredients.
Once they go out to be put in the compost pile, I add yard waste greens and browns so they even out to more-or-less correct ratio.